Starting switch



July 16, 1957 -2 Sheets-Sheet 1 Filed Aug. 25, 1954 7 H b. 4 3 w. an 1 Mlch my QR F m QM. MN Q N Q \m w 00 w \m N w m O0 w m. an b sq w w Y MNmm wwww N Q July 16, 1957' F. E. SCUTT STARTING SWITCH 2 Sheets-Sheet 2Filed Aug. 23, 1954.

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' STARTING swrrcrr Francis E. Scutt, Elmira, N. Y.,- assignor t- BendixAviation Corporation, SouthBend, Ind., a corporation of DelawareApplicationAu'g'ust23, 1954, Serial No. 451,381

9 Clairns. (Cl. zoo-#82) I This invention relates to a starting switchdevice for bustion engines.

the sta'r tirig'motor of a vehicle found in internal com- The startingswitch device embodying the present in-' f vention is adapted to beconnected in series with the ignition switch in a starting motorelectrical circuit and to be" actuatedby 'a vehicle control device, suchas the accel era'tor pedal orclutch. After the 'engine is starteda'suction'responsive'means is provided to prevent the starting switchfrom energizing the starting motor. i

In the past the reliability of switches of this type has been greatlyimpaired'by dirt and other air-borne impurities which cause the suctionresponsive means to stick either rendering starting impossible or to thestarting motor. i

It is -a principal object of the present invention to pro-- permittingdamage 1 vide a starting switch-having a'compact structure which isrelatively unaffected by dirt and other air-borne impurities. I Y iAnother object of this invention is to provide a selfcleaning means forat least a portion of the movable parts of a starting switch.

Still another object of the invention is to provide a 4 starting switchdevice which will remain energized during the cranking or startingperiod and which will remainde-energized under all possible operatingconditions of the engine.

The starting switch-device of the present invention consists of a rotoryieldably connected to the engine throttle shaft for rotation therewithto energize the switch and a suctionresponsive-member adapted to blockthe rotationof said rotor -during operation of the engine to preventenergizationof the switch, said rotor "being adapted torestrain'saidmember during the-startingperiod and-to urgesaid-membertoward and to aidinholding said member in blocking position during operation of theengine.

Other objects and advantages of the invention will be apparent to thoseskilled in the art from the following description when taken inconnection with the accompanying drawings, showing by way of example apreferred embodiment of the inventive idea.

Figure 1 is a top plan view of a portion of a conventional carburetorwith an enlarged sectional view of a starting switch embodying thepresent invention connected thereto;

Figure 2 is a View taken along the line 2-2 of Figure 1 showing theposition of switch parts when the throttle is closed and the engineinoperative;

Figure 3 is a view similar to Figure 2 showing the position of switchparts during engine cranking; and

Figure 4 is a view similar to Figure 2 showing the position of switchparts during engine operation with the throttle partially opened.

Referring to the drawings, numeral 10 designates a carburetor which maybe of conventional construction, 12 a throttle body, 14 a throttle valvemounted on a shaft 16 therein. A throttle lever 18 is secured to one endof 21,799,745 Patented July 16, 1957 W shaft 16 and is adapted to'beconnected to an accelerator pedal (not shown).

A starting switch 20 embodying the present invention is'p'rovided with ahousing 22 which may be cast integrally with the throttle body or may besecured thereto in any convenient manner. An opening 24 is located inthe wall of housing 22 to receive an extension of throttle shaft 16. Aninsulated terminal block 25 secured in the housing by a bolt 26 carriesa pair of electrical terminals 27 and 28. .The terminals extend throughsaid block and at their outer ends'are provided with flanges 30 and 32adapted to be connected to the starting motor electrical leads (notshown).

throttle shaft 16 and is provided with a plurality of projections orlugs 44, 46 and .48. A torsion spring 50 encircles the throttle "shaft16' and has one end hooked about a pin 52 secured to and projecting fromsaid' shaft.

The other'end of spring 50'abuts against lug .48 onjrotor 42'ther'ebyforming a direct yieldable link between throttle";

shaft 16and said'rotor. x

A conduit 54 connects a cylinder 56 formed .in ho us ing 22 with" thethrottle body 12 on the engine side of the throttle valve. At'on'e endcylinder 56'isclosed by a plug 58 andat theother endis provided with asleeve 60 which forms a seating surface for a ball '62. Ball62..

is vertically displaceable in a guide 64 which is provided with alongitudinal slot 66adapted to receive ing 44 on rotor 42. Lug 46onr'otor '42 projects .under' the guide 62 forms an abutment forlug 44asshown in Figure 4 and preventsfurther rotation' of rotor 42. Theinterior of housing 22 communicates with the atmosphere through port '68in the lower wall of the 'housi'ng'below guide 64;

A screen 70 is inserted in port 68to keep dirtand other air-borneimpurities from entering'the housing. The operation ofthe startingswitch device'is' as fol lows: With the throttle closed and the engineinoperativethe parts of the starting switch arein the position 7shoWn-inFigure 2 wherein ball-62 'rests'on lugAGfa'nd.

As the throttle valve is contacts 38 and 40 are open. moved towardopened position, rotor 42 is rotated in a counterclockwise directioncausing lug 48 to move contact 40 into engagement with contact 38 asshown in Figure 3. Engagement of the contacts energizes the startingmotor (not shown) to crank the engine. During the cranking period, theball 62 is restrained from responding to engine suction by lug 44 whichextends into the guide 64 over the ball.

After the engine starts, the throttle valve is returned toward closedposition whereby lug 44 is Withdrawn from the path of ball 62. At thesame time, lug 46 strikes ball 62 from below imparting an initial upwardmotion to the ball which continues to rise under the influence ofmanifold vacuum until seated in sleeve 60, Thereafter, when the throttleis opened, ball 62 forms an abutment for lug 44 and prevents rotor 42from moving contacts 38 and 40 into engagement.

Thus it can be seen that by utilizing a spherical-shaped suctionresponsive member and by providing for initial positive actuation of themember that my starting switch device is self-cleaning and its operationremains unaffected by dirt and other air-borne impurities. In additionthe rotor is provided with a direct yieldable connection with At theirinner ends the terminals are provided .with bosses 34 and 36 which earlyspring contacts 38 and40 respectively. L Rotor 42 is rotatably mountedon an extension of the throttle shaft whereby dependable operation ofthe switch is obtained. The relatively symmetrical arrangement of aminimum number of parts provides for an extremely compact'structure muchdesired for use on automotive engines.

While I have herein illustrated a preferred embodiment of my invention,it readily will be understood that numerous changes, modifications andsubstitution ofequivalents may be made therein without departing fromthe spirit and scope of my invention.

I claim:

1. In a starting switch device for an internal combustion engine havinga throttle shaft, a housing, electrical contacts in said housing, meanshaving a yieldable connection with said shaft and mounted in saidhousing for closing said contacts, a member movable in response toengine suction from an effective position to an ineffective position,said member when in said effective position being effective to preventsaid means from closing said contacts, means formed on said firstmentioned means for supporting said member in the ineffective positionand for preventing movement of said member to the effective position.

2. A starting switch comprising a housing, electrical contacts in saidhousing, a rotor in said housing rotatable to close said contacts, amember movable in one direction to an effective position to block saidrotor and prevent the closing of said contacts and movable in anotherdirection to an ineffective position, and projections on said rotoreffective when said rotor is in a predetermined position to limit themovement of said member in both directions.

3. A starting switch comprising a housing, electrical contacts in saidhousing, a shaft in said housing, a rotor rotatably mounted on saidshaft, a yieldable connection between said shaft and rotor, said rotorbeing rotatable to close said contact, a member movable in one directionto an effective position to block said rotor and prevent the closing ofsaid contacts and in another direction to an inefiective position, andprojections on said rotor effective when said rotor is in apredetermined position to limit the movement of said member in bothdirections.

4. A starting switch comprising a housing, electrical contacts in saidhousing, a shaft in said housing, a rotor rotatably mounted on saidshaft, a yieldable connection between said shaft and rotor, said rotorrotatable to close said contacts, a vertical guideway in said housing, aspherical member movable in said guideway between raised and loweredpositions, and a projection on said rotor movable in a path to beobstructed by said member in its raised position whereby said rotor isprevented from closing said contacts.

5. A starting switch comprising a housing, electrical contacts in saidhousing, a shaft in said housing, a rotor rotatably mounted on saidshaft, a yieldable connection between said shaft and rotor, said rotorrotatable to close said contacts, a vertical guideway in said housing, aspherical member movable in said guideway between raised and loweredpositions, and a projection on said rotor movable in a path to beobstructed by said member in its raised position whereby said rotor isprevented from closing said contacts, said projection also movable toobstruct said member in its lowered position.

6. A starting switch comprising a housing, electrical contacts in saidhousing, means in said housing movable to close said contacts, a membermovable to block said means and prevent the closing of said contacts,said means including a projection movable to obstruct said member whensaid means is in one position and a lug movable with said means to urgesaid member toward its blocking position when said means is in anotherposition.

7. A starting switch comprising a housing, electrical contacts in saidhousing, a shaft in said housing, a rotor rotatably mounted on saidshaft movable to close said contact, a spherical member in said housingmovable between raised and lowered position, a portion of said rotormovable in a path to be obstructed by said member when in its raisedposition to prevent the closing of said contacts and a projection onsaid rotor movable to urge said member toward raised position.

8. In a starting switch for an engine, electrical contacts, a movablemember for closing said contacts to start the engine, a vacuumresponsive member having two positions for controlling the operation ofsaid first mentioned member, and a means associated with said firstmentioned member for causing initial movement of said second mentionedmember toward one of said positions.

9. In a starting switch for an engine, electrical contacts, a movablemember for closing said contacts, a vacuum responsive member movablebetween an ineffective position and a position effective to control saidmember, and means associated with said first mentioned member forcausing initial movement of said second mentioned member from saidineffective position toward said efiective position.

References Cited in the file of this patent UNITED STATES PATENTS

